Scientists have finally decoded the chemical composition of the remarkably durable mortar used in the Maya city of Palenque. According to the Mesoamerican Science Review, the Maya added organic extracts from the bark of local Chukum trees to their lime-based mortar, creating a material that naturally seals cracks when exposed to rainwater.
This "biopolymeric" additive allowed the structures to survive centuries of tropical humidity and seismic activity. The research team is now looking at how these ancient sustainable building techniques could be applied to modern eco-friendly construction materials.